Recent content by quantum13

I think it's important to specify a direction for the momentum operator. I think that, if it's x-momentum and z-spin and you measure x-momentum to be zero every time then you know that the spin vector is probably in the x direction telling you for sure that z-spin is zero, meaning they don't...

I'm having a ton of trouble understanding how to solve diff eqs by using Fourier or laplace transforms to solve for the green's function, with boundary conditions included. I can understand the basics of green's function solutions, especially if transforms are not needed, but my textbook seems...

2nd year undergrad here. What did physics majors think about the difficulty of their various courses? I took the honors versions of the intro course and did pretty well but I'm in intermediate classical mechanics and it's destroying me... I guess taking six classes might have been a bit too...

What kind of math is needed for to understand general relativity? I don't understand the big difference between a senior undergrad and a first year grad student. Do grad students take those advanced math courses concurrently with GR or is it assumed they have more time to study?

There are tons of things you could do, all the engineering fields and even experimental physics could let you "design large physics or chemistry machines". Most people end up deciding based on some random factors, like getting an internship with a EE firm, scoring high on a CE test, having a...

A physics minor is probably a waste. Courses on quantum mechanics, lagrangian mechanics and maxwell's equations are going to do almost nothing for you when you sit down in front of a computer and write a graphics engine or design a cryptography system or machine learning algorithm. That said...

these are all interesting topics and i would personally like to learn about all of them. unfortunately if ur not a genius then it will take you a lot of time to study these topics and if you think you can just pile them on top of a typical engineering workload... try it for a semester and you...

inside the first sphere the potential is 0 or whatever it is to fit the boundary conditions because any 1/r^2 field is 0 inside a uniform spherical shell outside the second it's just q1+q2/r^2

You need some machinery about tensors and their transformation properties to prove this generally.

The "rate" of anything is just diving anything by time (or taking the time derivative) by definition Say you create a sound wave from a loudspeaker and blast it at a pool of water. The sound wave has some energy associated with it, because it consists of molecules bouncing around. You would...

Use gauss's law to find the formula for the electric field. E(a<r<b)=Q/4 pi r^2 Integrate this with your limits to find V(r) = Q/4 pi r

If the material requires more pressure to contract, that means it's fighting the contraction harder. So when a pressure (sound) wave passes through, the material hates being contracted and pushes the wave through, making it pass faster.

perfect solution, thanks

i'm using basic graphics on MATLAB where i use text(x,y,'text as string') to display text on a plot. is there a way to REMOVE this text? I tried overwriting it with ' ' and making the color white, font size 0, but none of these will remove the text.

I was reading a book on circuits and came across the phrase "a voltmeter can measure the voltage at a point with respect to ground" I don't actually understand what this is supposed to mean in circuitry though. Don't people usually refer to the voltage drop across a resistor? I suppose this...